Locomotive valve mechanism



Patented June 13, 1933 ALFRED w. Barton, 01? NEwYoRK, NQY.

Ilocoiuo'rivn VALVE mncnmmsm Application filed May 10,

This invention relates, generally, to mech anism for controlling the rate of flow of steam delivered to the cylinder, and relatively to the amount of cut-E of; the distribution valve, and to a method for effecting such control.

In accordance with usual practice many 10- eomotlves are deslgned to develop their maximum I. H. P. at anoperating speed of from to miles per hour, at which speed the developed tractive force is substantially all that weight on the drivers will permit without the drivers slipping. When such locomotives are started under long cut-ofi', the tractive power developed when the throttle is fully opened is too high for the weight on the drivers, and disadvantageous slipping of the drivers frequently occurs.

An object of the present invention is to pro vide means for simultaneously regulating the quantity of steam delivered to the cylinders descriptively to the specific embodiment in response to variations in the length of the cut-off of the distribution valves. For example, when the distribution valve functions der steam is increased to a predetermined maximum.

Another object of the invention is to operate such control means simultaneously in response to movement of the reverse gear.

1. Other objects of the invention will hereinafter appear.

In the accompanying drawing: Figure 1 is a side view of a locomotive, equipped with the invention; Fig. 2, a fragmentary side view showing details of the auxiliary control valve operating mechanism; Fig. 3, a transverse vertlcal sectlon showing detalls of the control mechanism; and, Fig. 1, a schematic view, showing various operating positions of the auxiliary control valve.

In the practice of the invention referrmg thereof herein exemplified, the locomotive comprises a holler 10, a reverse gear ll, steam chests 12, distribution valves 13, cylinders 14:, a throttle valve 15, and steam passages 16,

sufiicient to cause slipping. As the locomoi 1929. Serial 'No. 361,964.

pipes 16, adj acent'the steam chest. The lower end of each of the supply pipes 16 is made of increased internal diameter to provide a passage having a substantially uniform eifective transverse area when the valve is in central position. i l

In accordancewith usual locomotive practice the reverse gear functions when in full forward position to effect a long cut-off by V the distribution valves, and when? varied from that position, to shorten the cut-off as desired. The. present invention provides means which simultaneously functions in di-. rect response to movements of the reverse gear to-regulate the amount of opening of the auxiliary or butterfly valves 17, in inverse proportion to the amount of the cutofl by the distribution valves, so as to reduce the rate of flow of cylinder steam to a predetermined minimum when the distribution valves are operating with long cut-ofi', and to increase the-rate of flow. of cylinder steam to a predetermined maximum when the distribution valves are operating with short cutoff. To this end, each butterfly valve (is mounted for rotatory movementon a pintle 17a, providedat one end with a lever arm 17?). v The lower end of the lever arm is pivotally H connected to one of the bifurcated ends of a rod 17 c. The other end of the rod is p-ivotal- 1y connected to an extensionlla, on the reach rod' llb. An additional lever 110 is provided at the opposite end of the reverse shaft from the usual reverse shaft lever, to operate the butterfly valve on. that side of the locomotive. a l

The operationof the mechanism, is as follows. When the locomotive is at full stop and the distribution valves are set for long G cut-off. the butterflyvalve is'at'aposition to restrict the supply of steam admitted to the chest to a predetermined minimum suchthat theforce exerted bvthe drivers will not be tive picks up speed,the reverse gear is operated so as to shorten the cut-off, then. the butterfly valves are by the same operation, simultaneously moved so as to increase the amount of steam fed to the chests in inverse proportion to the shortening of the cut-off. When the reverse lever is ultimately moved to shortest cut-off position, the butterfly valves are fully open permitting the maxi mum quantity of steam to enter the chests.

An important advantage of the present invention is that the rate of flow of cylinder steam is simultaneously regulated in response to variations in the degree of cut-off of the distribution valves, to an amount which will not produce slipping of the drivers. I

While one of the preferred forms of the invention has been described, it is to be understood that various modifications in form,

arrangement, and procedure may be resorted to, Without departing from the spirit and scope of the invention embraced in the following claims. 7

The invention claimed and desired to be secured by Letters Patent is: i

1. In a locomotive, the combination of a throttle valve; a steam chest; a distribution valve in said chest adapted for variable cutofis; means for conducting steam from the throttle valve to the steam chest; an auxiliary valve for regulating the flow of steam through said conducting means, comprising a plate therein, a pivot for the plate, and a lever adapted to rotate the pivot to vary the position of the plate; a reverse gear, comprising a reverse shaft, a reverse lever, and a reverse arm on said shaft; means operative by the reverse arms to vary the cut-off of the distribution valve; and a rod connected at one end with the reverse lever and at its other end to the auxiliary valve lever, whereby the degree of opening of the auxiliary valve will be varied in response to variations in the amount of cut-off of the distribution valve.

2. In a locomotive, the combination of a working cylinder; a distribution valve therefor adapted for variable cut-offs and for reversing the direction of operation of the Working cylinder; a source of steam supply; a conduit for conducting steam from said source to said distribution valve; an auxiliary valve in said conduit; a main throttle valve in said conduit between said auxiliary valve and said source for controlling the flow of steam from said source to said auxiliary valve; valve gear and reverse gear mechanism for controlling the cut-off of the distributlon valve and for controlling the direction of operation of the working cylinder,

including ashaft rotatable at either side of holding said shaft in adjusted position; and

ALFRED W. BRUCE. 

